Hi Jim: thanks for the picture of the mountains in your PA area ... that's so beautiful !! I live 1/2 hour northeast from DeKalb, IL. You are right that DeKalb is flat, mostly corn fields. I have more trees & and varied scenery here. My heavy clay is fertile too. I don't need to fertilize much, but I need to add trace elements for disease-resistance. This is my first year WITHOUT horse manure, and it's the most black spots, and disappointing year !! Horse manure NPK is low, but high in trace elements, thanks to its being a good source of bacteria. Plus zinc and copper vitamins added to the feed. Even if the soil is tested sufficient in NPK, with constant rain, and after heavy blooming .. nitrogen and potassium are leached out. Nitrogen can be re-supplied again with nitrogen-fixing bacteria, which is abundant in organic matter like composted manure. But potassium has to be supplied via fertilizer. Henry Kuska, professor of chemistry and once had a garden of over 1,000 roses, made an excellent observation that perhaps roses become depleted of potassium after a bloom cycle, esp. late fall. I agree, I gave Comte de Chambord a big-dose of potassium at the start of its 2nd flush ... it gave many petals-bloom, and the bulk of the blooms are heavier than the leaves plus the wimpy root. Now at the end of its flush, it's breaking out in B.S. To make zillion-petals bloom, a lot of potassium and calcium are needed prior to each flush. Less-petals like Knock-out are more disease-resistant, because the bulk of its roots is more than the bulk of the blooms ... the roots can easily fetch more nutrients. So for wimpy-root roses like Comte de Chambord and Jude the Obscure, immediate soluble fertilizer is needed for blooms & disease-protection. Why Mr. Lincoln is more disease-resistant for your soil than else where? Perhaps Mr. Lincoln root is most vigorous in your particular soil to fetch the nutrients needed to fight against diseases. Romanticas are clean in my alkaline soil, since their roots are very vigorous at my soil pH, with plenty of dolomitic lime for them. Your pic. shows the mountains in PA, which means less air-flow than my open Chicagoland. Plus I don't get dew, as you stated, "Here we get heavy dews outside. So around 10pm the leaves on our roses are getting wet as if it rained. They dry off early to late morning so perfect breeding grounds for BS." I find that dry & leathery leaves like Crimson Glory (prone to mildew in dry climate) tolerate wetness on its leaves. Crimson Glory is my top-clean rose, even after 1-week of constant rain. Same with shiny leaves like Pat Austin ... that one is known as a water-hog & loves the rain, but become droopy in hot & dry weather. Christopher Marlow has thick & shiny & rain-resistant leaves. It's the thin-leaves like Comte de Chambord that can't take the humidity nor wetness. I have to give that SOLUBLE calcium & potassium to make its leaves thicker. Same with Gruss an Teplitz, leaves can't take wetness, and he's the parent of Dr. Huey rootstock. Zinc and copper are the 2 strongest antifungal agents, and some soil are more deficient in those. That's why this year without horse manure, my roses are the worst ever. Calcium is a weaker antifungal agent, but it still works. That's why my Duchess de Rohan planted in my clay fixed with tons of gypsum, is 100% clean despite being a shady, perpetually wet spot where other perennials are mildewed, and other roses with BS. My clay is dolomitic lime, and I'm next to a limestone quarry, yet my soil is tested barely adequate in calcium. One hundred plus-petals bloom like Austin roses require lots of calcium and potassium, versus less-petal Knock-out. Below is a bouquet picked today, July 23, showing the many petals roses. The firm-petal one like Stephen Big Purple which lasts long in the vase, also requires an ungodly amount of calcium. It does very well next to my limestone-based patio, and doubled in growth after application of gritty lime. Pink is Sonia Rykiel, yellow is Golden Celebration, small beige Mary Magdalene, big peachy pink are Evelyn. This post was edited by Strawberryhill on Wed, Jul 23, 14 at 22:56

Khalid wrote in another thread: "Then I stopped spraying even any organic matter. I gave more calcium to my roses which made the soft branches and leaves harder thus making it relatively unattractive for the pests. This reduced the affected bushes / leaves to a good extent." Agree with Khalid, folks in rainy climate lime their soil, either in late fall or early spring, depending on how many inches of rain they get. Rain is acidic at pH 5.6, as the pH drops, less calcium and potassium are available. The best lime to use is Espoma Garden Lime (sold at Walmart for $10 per 5 lb.). It has 20% calcium and 10% magnesium ... both are essential in keeping leaves thick so pests cannot invade. From the above chart, around pH 5.6 (rain water), less molybdenum, less magnesium, less calcium are available. Next nutrients that are less: phosphorus, potassium, and nitrogen. I already posted in Organic Rose my experiment that I did with 2 identical Thai basil: I lowered the pH of one with acidic cracked corn (pH 4), plus gypsum (17% sulfur) .. that Thai basil' leaves became pale, plus THINNER due to less calcium and magnesium available. Then I saw blackspots on a Thai basil for the 1st time !! The other basil I planted in my alkaline clay (pH near 8), and it's twice taller plus really thick & glossy leaves (more available nitrogen, potassium, sulfur, calcium, and magnesium). But leaves were just a bit pale due to less iron at high pH, so I gave it blood meal, has chelated iron, and leaves became dark green. I once planted a bok-choy vegetable next to my patio with a limestone base, so the soil is very alkaline, pH 8. The leaves were dark-green, but its so tough that I boiled it for one hour, and it's STILL so fibrous that my teeth can't handle, let alone some tiny pests like aphids, rose slugs, or midge. Rose slugs (sawfly larvae) are very rare in my alkaline clay, unless I lower the pH with my experiments: Put acidic cracked corn (pH 4) in potting soil, and roses got rose-slugs from THINNER LEAVES in acidic rain (calcium, magnesium, and potassium drops when pH drops). Mirandy rose got a big-fat rose-slug on it for the 1st time. Why? It's next to a tree, and the tree robs the soil of calcium, magnesium, and potassium. Plus tree roots secret acid, so the soil became even more acidic with rain (pH of rain is 5.6). Used molasses, plus vinegar, plus sulfate of potash (21% sulfur), plus gypsum (17% sulfur) ... such acidic solution made leaves thinner, plus the stinky molasses really attract sawfly which give birth to rose-slugs. CONCLUSION: The best solution for pests is to raise soil pH by using dolomitic lime such as Espoma Garden lime (20% calcium and 10% magnesium). My soil is dolomitic clay, so I don't have midge, rose-slugs (sawfly larvae), nor aphids, unless I use acidic fertilizer. When there's tons of acidic rain, I throw pea-gravel on top of roses that like it alkaline, pea-gravel has many alkaline minerals to make leaves thick, glossy, and to prevent pests.

Might be my fault Dan. I was temped to say something about digging up old threads just to be controversial but bit my tongue. ;) But I only threw in the "organic" on pest controls to distinguish them from synthetic pesticides because the milk advocates always come back with "it's better to use milk then to use chems". Also wanted to point out that it was raw milk - not available to most - Dixie was advocating. The bacterial count and types in raw is substantially different from that in pasteurized so pasteurized milk has even less potential value to plants than raw. Dave

Conditions *don't* seem to be getting any better for life as a whole, do they? Garden-wise I battled a horrific disease in my tomatoes last year...14 plants over 7' tall and healthy-looking as you'd want produced tons of blooms and tomatoes...and every single tomato rotted. Those were all open-pollinated/heirlooms. A very frustrating adventure. Being a rookie I did not spray or other wise try disease control other than trimming the lower leaves. Last year was a hot and wet year. This year I planted around 90% hybrids and they're looking good and large tomatoes are developing nicely...so far. I also planted a couple of Bumble Bee Mix "artisan" op plants. I've already pulled one BBM due to "something" starting to kill it...irregular brown spots on leaves, shriveling leaves, tops dieing out, etc.,...the green fruit looked good, though. After pulling that one a couple of days later I've found the other BBM exhibiting the same symptoms (no surprise as it was planted beside the other one). I'll be pulling it this afternoon. I have one other OP plant which is a Brandywine Red that is planted at the other end of the row. So far it appears to be (mostly) dodging blight, fungus, disease, whatever. All the plants are showing a touch of yellow in the lower leaves. The plants are trimmed up to around 12" from ground and I will probably trim them a bit more. I sprayed (first time) with Serenade last Saturday...only to have a thunderstorm move in a few minutes later and eventually dump about 1/2" of rain on us.<sigh> The weather has been very hospitable to diseases...hot and very humid. The weather forecast is for sunshine this week and dropping humidity, then rain this weekend. The sunshine is *most* welcome!!! My goal for after work today is to pulled the remaining Bumble Bee and to respray the Serenade...I feel the first application pretty well got washed off. But, yes, I can see how pestilence and disease is becoming more widespread as time goes on. A sign of the times...